fix gc dry run issue

[wy65701436]

In the dry run mode, the accessories should be considered when try to simulate delete the subject manifest.

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Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

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• Well Written Title and Summary of the PR
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[codecov]

Codecov Report

Merging #19208 (44291d5) into main (c7e2529) will decrease coverage by 0.01%.
The diff coverage is 5.88%.

@@            Coverage Diff             @@
##             main   #19208      +/-   ##
==========================================
- Coverage   67.39%   67.38%   -0.01%     
==========================================
  Files         993      993              
  Lines      108888   108896       +8     
  Branches     2751     2751              
==========================================
+ Hits        73382    73383       +1     
- Misses      31561    31571      +10     
+ Partials     3945     3942       -3     

Flag	Coverage Δ
unittests	67.38% <5.88%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files Changed	Coverage Δ
src/jobservice/job/impl/gc/garbage_collection.go	45.43% <5.88%> (-0.52%)	⬇️

... and 7 files with indirect coverage changes

[chlins]

lgtm